Boss Endurance and Cake
By completing the game you can unlock Boss Endurance mode for Minigame and a Cake for your collection.
Boss Endurance: Complete the game once.
Cake for collection: Complete the game once.
Time Attack Mode
To unlock Time Attack mode you must collect all 120 chests throughout the game.
Hidden Birthday Message
On your birthday, play the game. After the startup sequence, there will be a brief 'Happy Birthday!' message decorated with various Kirby characters.
Extra Mode
To unlock extra mode you must collect all 120 chests throughout the game.